介电力显微术：一种观察纳米材料中电荷行为的新方法

功能纳米器件中组成材料间的电荷转移输运过程对于器件中的物理化学过程以及由此引发的器件功能会有重大影响，因此，深入理解器件工作过程中的电子／离子行为机理对于优化器件功能以及进一步开发纳米材料的应用潜力具有重要意义．传统场效应晶体管对于纳米材料的电输运测量表征反映了载流子在整个器件中的统计行为，但难以检测电荷具体的转移输运过程．同时，由于纳米材料的尺寸和分散性，基于纳米材料的场效应晶体管面临着制备困难、电极／纳米材料接触复杂和制作成本高等问题．因此，本课题组发展了介电力显微术（dielectricforcemicroscopy，DFM）方法并实现了对纳米材料电学性质的无接触、高空间分辨率和快速表征．本文介绍了介电力显微术的基本原理，列举了其在探究一维纳米材料、纳米颗粒以及有机半导体薄膜电学性质上的一些应用实例．这些实例验证了介电力显微术对纳米材料电学性质的表征能力，并展现了这一技术在纳米材料物理化学性质和纳米器件功能研究上的广阔前景．

Dielectric force microscopy： A new approach for observing charge behavior in nanomaterials

The behavior of charges transferring between the components of functional nanodevices would significantly impacts the physical/chemical process in the devices. Thus, comprehensively understanding the transfer behavior of electrons/ions in the operational devices is essential for optimizing the performance of functional nanodevices and exploring the application potential of nanomaterials. In general, the measurement results of field effect transistor （FET） present the statistic behavior of the carriers in the whole nanodevices, so the FET is powerless to observe the details of transfer process of charges. In addition, there are some drawbacks for the FET based on nanomaterials, such as difficult fabrication, complex electrode/nanomaterials contact and high costs. Therefore, we developed the dielectric force microscopy （DFM） to solve these problems. In this paper, we introduce the principle of DFM, and show some applications of interpreting how contactless DFM technique can quickly characterize the electrical properties of nanomaterials, such as one-dimension nanomaterials, nanoparticles and organic semiconducting film, with high spatial resolution. These applications demonstrate the capabilities of DFM for the characterization of the electrical properties of nanomaterials, and present the broad prospects of DFM in the research about the physical and chemical properties of nanomaterials and the performance of nanodevices.